1. Technical Field
The invention is related to a system that incorporates a whiteboard into a projector-camera system. More particularly, this invention is related to a system and method for transmitting a clear image of a whiteboard work surface for remote collaboration by employing a visual echo cancellation technique.
2. Related Art
During the past few years one has witnessed the transformation of video cameras and projectors from expensive lab equipments to affordable consumer products. This has triggered the creation of many human-computer interaction systems that incorporate both the large-scale display provided by the projector and intelligent feedback from one or more cameras. On the other hand, the whiteboard is still an indispensable part of many meetings (including lecturing, presentations and brainstorming), because it provides a large shared space for meeting participants to focus their attention and express and exchange their ideas spontaneously.
Previous works have integrated whiteboards within a projector-camera system. However, these previous works mostly focused on group collaboration at the same physical location. The use of a whiteboard where there are remote participants, on the other hand, poses a variety of problems. For example, remote meeting participants cannot contribute to the content written on a whiteboard because they are not physically in the same place as the whiteboard. Additionally, sending images of the whiteboard to remote participants via a network use a great amount of network bandwidth and is often quite slow.
Therefore, what is needed is a system and method for capturing and transmitting the contents of writing on a whiteboard that can be transferred to remote meeting participants via a network in a legible manner without requiring a large bandwidth. The system should also allow remote participants to contribute to the whiteboard content and allow for the whiteboard content to be archived for viewing at a later date.